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The algae of water basins i Novohradské hory
PLOCOVÁ, Alena
This thesis deals with six ponds, artificial snall lakes, (Mlýnský, Huťský, Pohořský, Uhlišťský rybník, Zlatá Ktiš a Kapelung) in the Novohradské mountains. They were studied at the interval of years 2004-2006. The basic hydrochemistries and variety of species of planktonic Algae and Cyanobacteria were analysed there. The volume of NH4-N was the highest in Mlýnský pond (20-76 ?g/l), which proves for a recent organic pollution. In other cases the rate was in range of 13-53 ?g/l. The most of NO2-N was again found in Mlýnský pond where its rate reached up to 420 ?g/l. The total amount of t-P was of the same rate in all the sites. It differed only slightly- 58-91 ?g/l. From the hydrochemical data follows that the most nutrients loaded is Mlýnský pond and the cleanest is Pohořský one The transparency (Seccki depth) of all the localities is also high (76-200 cm). It can be compared to the lakes of the Bavarian Forrest and the Bohemia Forest (Šumava). The proportion of N/P is usually between 7,0-29,8 (Chart 11), which shows evidence of limiting P (the most common limiting factor for phytoplankton in fresh waters). The total amount of found taxa (98) is comparable to e.g. lakes of the Bohemia Forest (260), this ara is however more explored. The largest amount of species is at Huťský pond (38) and the smallest one is at Uhlišťský pond (17). As a new species for the the Czech Republik was found Staurastrum arctiscon and Phaeospaera gelatinosa, than another interesting discovery is Vacuolaria penardii and Chloromonas nivalis (Scotiella nivalis). Also Dicranochaete sp. and Paulinella chromatophora are noticeable. The ponds of the Novohradské mountains are from the point ob view of hydrochemistry view unigue habitats. They make for refugium oligotrophic, rare and interesting species of Cyanobacteria and Algea and that is why they deserve proper protection.
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Accuracy of successive removal method
Konečná, G. ; Janáč, Michal ; Jurajda, Pavel
Accuracy of successive removal method for two different localities (a trout brook and a smaller lowland river) was examined. Our aim was to define optimal sampling effort to get reasonable results of fish assemblage parameters (species richness, species relative abundance, abundance). Estimates of population and assemblage size were made using the Leslie and Davis graphic method. On the trout brook and the lowland river locality, time cost of the sampling was evaluated. Our suggestion is that one succesive removal pass is the optimal sampling effort for the trout brook, two passes are needed on the smaller lowland river for optimal description of assemblage parameters. More passes are necessary if population size estimates are made and in assemblages with less catchable species.
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